Discharging container with a filter and a bottle stopper for use in the container

ABSTRACT

The present invention provides a discharging container whose main part is a squeeze-bottle adapted for use as eyedroppers and transparent to such a degree as required. This container has to perfectly shut off ambient air and bacteria not to flowing into a liquid content of the container so as to keep it sterilized even after unsealed for use.  
     The discharging container has a laminated bottle  2 , and a stopper  3  attached to a finish  2   a  of the laminated bottle, the bottle being composed of an outer layer  21  and an inner layer  22  delaminating from the outer layer  21 . A vent hole  4  is formed in the outer layer so as to introduce ambient air in between the outer and inner layers  21, 22 . A discharging passage  10  is formed in the stopper  3  so as to exude through it a liquid content inside the inner layer  22 , and the stopper further has a check valve  8  and a filter  7  disposed on the downstream side of the valve.

FIELD OF THE INVENTION

[0001] The present invention relates to a discharging container having afilter and adapted for use as an aseptic eyedropper, and also to astopper for closing the container. Particularly, the invention relatesto a discharging container comprising a stopper and a laminated bottleincluding a delaminatable inner layer such that a liquid medicine storedtherein can flow out without allowing any amount of ambient air to flowinto the bottle.

BACKGROUND OF THE INVENTION

[0002] Collyria are solutions or liquid suspensions of ophthalmologicmedicines, that may alternativey be dissolved or suspended in time ofuse. Such collyria are kept sterilized for application to conjunctivalsac, and the term “collyria” used herein includes eyewashes.

[0003] Collyria are dozes to eyes that are one of the most delicateorgans in ever human body, and inflamed eyes are most sensitive toforeign matters. Therefore, preparation of collyria has to be done verycarefully in order to keep an aseptic condition such that not only anypathogenic bacteria are alive but also any harmless bacteria are shutout completely. Even such an aseptic condition is not satisfactory, butcollyria must be prepared milch more carefully lest they should becontaminated with any pyrogens and/or any amount of insoluble foreignmatters.

[0004] Generally, eyedropping squeeze-bottles (viz., eyedroppingcontainers) contain therein collyria to be distributed to users for useas eyedroppers The bodies of such eyedropping bottles are usually formedof plastics, and proper examples thereof are polyethylenes,polypropylenes, polycarbonates, polyarylates and polyethyleneterephthalates. In case of such collyrium-containers, it is veryimportant requirements that they be transparent to such a degree asenabling visual check of foreign matters from outside, and has a lowpermeability for vapor so as to avoid concentration of collyria due tovaporization loss of water in the container. In addition, many proposalswere made to improve the prior art eyedropping containers so as tosurely prevent bacteria or the like foreign matters from entering thecontainers and thereby rendering them non-sterilized in usage as well asin distribution. Further, those prior proposals were designed todisinfect any bacteria accidentally present in the collyria beingdropped into eyes.

[0005] For the purpose of sterilizing containers once unsealed, certainreserving agents may be added to collyria (viz., contents of thecontainers). Examples employable as such reserving agents are polymixinsulfates, quarternary ammonium compounds, chlorobutanols, organicmercury compounds, esters of p-hydroxybenzoic acid and alcoholicderivatives thereof. These reseving agents will, despite their excellenteffect of killing microbe and bacteria, possibly cause variousophthalmogical inflammation or other serious damages after repeated use.Allergic reaction may be caused to some contact lens wearers even byreserving agents contained in low concentration.

[0006] Certain filters have been proposed to selectively remove suchmedically ineffective additives. These filters will remove saidineffective additives from the liquid medicine (viz., a collyrium)flowing through a dispensing passage in a bottle before discharged in adropping manner. Japanese Patent Laying-Open Gazettes No. 4-297264 andNo. 6-14972 describe such a filter that is disposed in the dispensingpassage formed through each eyedropper. These prior art eyedroppers willhowever fail to diminish the concentration of the reserving agentssufficiently if they are contained rich enough to ensure a satisfactorysterilization effect. Since those prior art eyedroppers are of such astructure that bacteria are not shut out but carried by ambient air intothe collyria, concentration of the reserving agents cannot be made lowbut has to be high enough to disinfect such a contaminated collyria. Asa result, a noticeable amount of the reserving agents will unavoidablyremain in the collyria having passed the filter before dropped.

[0007] On the other hand, Japanese Utility Model Gazette No. 63-184037discloses a certain hydrophilic permeable membrane that is disposed in adischarging aperture through which eye drops filled in a container bodyarc exuded. This membrane allows the eye drops to pass through it, butstops bacteria and air not to flow into the container body. Thecontainer body in this utility model may be a tube having a depressedend, or be shaped foldable into a depressed configuration so that innervolume of said body gradually decreases as its content is consumed. Inthis type of prior art eyedropper, flow of ambient air into thecontainer is prevented perfectly, protecting the liquid medicine fromcontamination with bacteria, thus realizing a lowest possibleconcentration of reserving agents to be added to said medicine. Sincethe container body of a monolayer structure has to deform itselfplastically, it will be difficult to mold it using any plastics. Thus,aluminium tubes or the like must be used to manufacture such containerbodies, thereby rendering them untransparent against the general rulesprescribed for eyedroppers in the Japanese Pharmacopoeia. In addition,such container bodies that will become depressed more and more along thecourse of usage are difficult to stand upright during storage and lessconvenient to use.

[0008] An object of the present invention made in view of thesedrawbacks is therefor to provide a discharging container comprising asqueeze-bottle adapted for use as eyedroppers and capable of satisfyingthe transparency requirement. This discharging container must beimproved to perfectly shut off ambient air and bacteria not to flowinginto a liquid content retained in the container. This means that suchcontainer has to be kept sterilized even after unsealed for use. Anotherobject of the invention is to provide a stopper designed to be used insuch a discharging container.

DISCLOSURE OF THE INVENTION

[0009] A discharging container with a filter provided herein comprises alaminated bottle and a stopper attached to a finish of the laminatedbottle, wherein the bottle is composed of an outer layer and an innerlayer delaminatable therefrom. A vent hole is formed in the outer layerso as to introduce ambient air in between the outer and inner layers. Adischarging passage is formed in the stopper to exude therethrough aliquid content retained inside the inner layer, with the filter beingdisposed together with a check valve in the discharging passage.

[0010] In use, the check valve will inhibit ambient air from enteringthe space defined by and in the inner layer. Consequently, the innerlayer will deflate as the liquid content is consumed, with the liquidcontent being protected from contamination with bacteria which wouldotherwise be carried by ambient air into that space. Ambient air ishowever allowed to flow inwards in between the outer and inner layersthrough the vent hole, so that the outer layer once pressed with fingersor the like to exude the liquid content will restore its normal shapedue to elastic recovery, until the container becomes empty. Thecontainer of the invention maintains its outer configuration unchangedfrom the beginning to end of usage, thereby enabling it to stand uprightduring storage and rendering it more convenient to use. Since the innerlayer deflates and ambient air is prevented from flowing into the innerlayer as mentioned above, despite gradual consumption of the liquidcontent, any reserving agents need not be added for the purpose ofdurable sterilization. Further, any resin materials may be employed tomanufacture the inner and outer layers, if they are transparent to therequired degree and do function as a good gas barrier and a good watervapor barrier. Thanks to these features, the container will showexcellent performances as an eyedropper.

[0011] Preferably, a further check valve may be disposed in the venthole so as to permit ambient air to flow in a space defined by andbetween the inner and outer layers and to prevent the ambient air havingentered this space from flowing out through the outer layer. If such afurther check valve is incorporated, then the squeezing of the outerlayer will compress the air held in that space to raise its pressure,which in turn will depress the inner layer to exude the liquid contentthrough the discharging passage. If contrarily no such check valve isemployed, then users of this container will need to close the vent holewith their fingers or the like when they squeeze the outer layer ofcontainer.

[0012] The container of the invention has in its discharging passage thefilter as discussed above, so that the bacteria floating within ambientair are stopped not to enter the bottle through said passage. Thanks tothis feature, the interior of this bottle once opened will be keptsterilized even in a case wherein a very slight or no amount at all ofreserving agent is added to the content. In another case whereinsignificant quantities of reserving agents are used to be present in theliquid content, the filter may preferably be designed such that bacteriaare inhibited from passing through it and reserving agents areselectively removed from it.

[0013] The filter may be located downstreamly of the check valve firstmentioned above. The liquid content portion stagnant around the checkvalve, particularly in the downstream side thereof, is also protected bythe filter so as not to contact the ambient air. Bacteria will thus beinhibited to propagate in the stagnant portion of liquid content,thereby making it possible to secure a sufficient space between thecheck valve and the filter wide enough to allow the check valve to besmoothly opened and closed, with the space being protected from thebreeding or propagation of bacteria.

[0014] The stopper which the present invention provides from anotheraspect is one to be attached to a finish of the bottle and does comprisea discharging passage for dispensing a liquid content held in thebottle, a check valve disposed in the discharging passage, and a filteralso incorporated therein and located downstreamly of check valve.

[0015] The check valve may have a valve hole constituting a part of thedischarging passage and a valve body for closing the valve hole from itsdownstream side, wherein the valve body closing the valve hole can bedisplaced downstreamly to open it. A free space is defined between thevalve hole and the filter so as to permit displacement of the valvebody.

[0016] The valve body may be formed integral with a cylindrical member,disposed between the valve hole and the filter so that this member holdsthe filter in place in the passage.

[0017] A deformable thin piece or pieces may connect the cylindricalmember to the valve body continuing therefrom.

[0018] The filter may be formed such that bacteria are inhibited frompassing from the downstream side to the upstream side of the filter.

[0019] The discharging passage may have, downstreamly of the filter, aregion whose volume is not larger than one drop of the liquid contentbeing exuded dropwise out of said passage.

[0020] The bottle may comprise a cap attachable to the bottle's finish,with a projection protruding from the cap so as to fit in and engagewith the discharging passage region located downstreamly of the filter.The stopper according to the invention in this case may have, as thepassage region located at downstream side of the filter, a cavity thatwill be fully occupied by the projection.

[0021] The check valve may be designed such that inward flow of theambient air into the bottle is prevented but the liquid content of thebottle can flow out of the bottle.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022]FIG. 1 is a cross-sectional side elevation of an eyedropperprovided in an embodiment of the present invention;

[0023]FIG. 2 is a partly fragmentary cross-sectional front elevation ofthe eyedropper shown in FIG. 1; and

[0024]FIG. 3 is a fragmentary view seen along the arrow line A-A to showa check valve incorporated in the eyedropper of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

[0025] The discharging container of the invention may be utilized as anymedicine container such as an eyedropper, or as any cosmetics containeror the like. The container may comprise at least the bottle and thestopper, and may additionally comprise an external cap covering thestopper and closing a discharging passage formed therein.

[0026] The delaminatable laminated bottle may substantially consist of afinish and a body, and these may be formed by the injection blow-moldingmethod, the direct blow-molding method, the injection molding or thelike proper method. An inner preform may be made as a discrete member(viz., inner parison) to be inserted in an outer preform also madealready as another member (viz., outer parison). A combination of thesediscrete parisons (viz., a composite parison) thus prepared will then besubjected to the blow-molding process to give the delaminatablelaminated bottle, so that its inner layer is laminated on its outerlayer over its full height including its finish and body. The finish maypreferably be made considerably thicker and more rigid than the body, bymaking thicker portions of the inner and outer layers to give thefinish. On the other hand, bottle body may preferably be designed suchthat its outer layer is capable of squeezing and elastic recovery, withits inner layer forming a film ready to deflate as the liquid content isconsumed. Each of such inner and outer layers may be a monolayerstructure, or alternatively be of a multilayer structure.

[0027] The bottle's inner layer may be formed of any proper resinmaterial, for example a polyolefin such as a polyethylene (PE) and apolypropylene (PP). The bottle's outer layer may also be formed of anyproper resin material, for example a saturated polyester resin such as apolyethylene terephthalate (PET) and a polyethylene naphthalate (PEN),or alternatively be formed of a soft glass. In a case wherein thecontainer is to be used as an eyedropper, those materials for the innerand outer layers are selected to make it as transparent as possible andless impermeable for water vapor. In particular, the raw material forthe inner layer brought into direct contact with a medicine as thecontent of said container must be a resin (such as PE) of a higherchemical resistance. The raw material for the outer layer may preferablybe a resin (such as PET or soft glass) that is highly transparent andless permeable for water.

[0028] The laminated bottles each consisting of an outer PET layer andan inner PE layer are suited to the so-called EO sterilization method.The most serious problem inherent in this method is that a noticeableamount of EO gas (viz., ethylene oxide gas) tends to remain in theresins forming the bottles, probably resulting in elution into theliquid content to thereby chemically reacting with components of theliquid content. PE, PP and the like are effective to diminish residue ofEO and facilitate it elute, so that the inner layer made of such a PE orPP will bring a lesser quantity of EO migrated into the liquid content.A lower water permeability through the PE inner layer will suppressvaporization of water not to condense the content. The relativelythicker outer layer may be formed of a PET highly transparent and lesspermeable for gases and water will render the bottle as whole moretransparent and less permeable for gases and water. Thus, the innerlayer will be made of a material that is more resistant to chemicals,i.e., medicines as the content of the bottle, and less permeable forwater. As for the outer layer, it will be made of another materialfacilitating its delamination from the inner layer and having a higherstrength and squeezability. Different materials of different propertiescan be used to form the layers to give the eyedroppers of a betterperformance as a whole.

[0029] The vent hole preferably having a check valve incorporatedtherein may either be formed in a finish, a body or a bottom of theouter layer. The check valve may be of any proper structure, and forexample a plug-shaped valve body may be employed to fit in the vent holeof the outer layer, or the inner layer itself may be designed tofunction as the check valve. In the last case, a portion of the innerlayer will close the vent hole from inside in such a state that when anegative pressure is produced in the space between the outer and innerlayers the atmospheric pressure in the ambient air will deform the innerlayer portion inwards and open the vent hole, thus serving as a checkvalve. Such an inner layer portion preferably shows elastic recovery tospontaneously restore its normal state in which it closes the vent hole.In a case wherein the vent hole is formed in the finish of the outerlayer, the inner layer portion for closing the vent hole may be madethicker than the body portion of this inner layer. The thinner bodyportion of the inner layer will deflate as the amount of content reducesduring use of this container.

[0030] The vent hole having a diameter considerably smaller than thedischarging passage may dispense with any check valve. The squeezed bodyportion of outer layer will in this case compress the air presentbetween it and the inner layer, to consequently compress the latter toexude the content through said passage in a dropping manner. Bysqueezing for instance the bottle body whose content has been consumedto a considerable extent, its volume will decrease at a higher rate thanthe interlayer air being exhausted out of the space between the outerand inner layers, through the vent hole, which has a small diameter, forexample, of about 0.1 to 0.5 mm. Thus, the interlayer air is compressedto depress the inner layer centripetally to deflate so that the contentis forced outwards through the discharging passage formed in thestopper. Effective cross-sectional area of this passage may be designedmuch larger than the opening of said vent hole such that the resistanceto the liquid content being exuded through the passage is rendered muchweaker than the resistance to the air being temporarily ventilated out.Preferably, for smooth discharge of the liquid content, thefirst-mentioned check, valve in the discharging passage in this case maybe designed not to encounter any noticeable resistance when beingopened.

[0031] The stopper according to the invention may either be a one-piecemember, or a composite member consisting of two or more parts.Preferably, this stopper fitted in or on the finish of bottle maycomprise a discharging (viz., dropping) nozzle protruding upwards sothat the discharging passage extends axially along the axis of thisnozzle.

[0032] The compulsory check valve may comprise a valve body that isdisposed downstream of the valve hole to be closed with this valve body.The valve hole may be formed in a partition that is formed at anupstream end or intermediate between it and downstream end of thedischarging, passage. The partition may either be formed integral withthe stopper, or alternatively be a discrete member to be securedthereto. The valve body normally closing the valve hole will be shiftedto its downstream position to open said hole. A sufficient space forallowing such a displacement of the valve body may be provided betweenthe valve hole and the filter. Even if any residue of the liquid contentwould stay in this space, bacteria is prevented from mixing in theresidue, as the space is shut off from the ambient air by the filter.

[0033] The valve body may be an integral portion of a cylindrical memberarranged between the valve hole and the filter. Deformable thin piecesmay integrally connect the valve body to the cylindrical member,allowing this body to displace up and down relative to this member. Thecylindrical member may be shaped to support the filter in place so as toafford the sufficient space noted above for the displacement of valvebody.

[0034] The filter for preventing bacteria from undesirably entering theupstream side from the downstream side thereof may for example be amembrane filter, a sintered plate, a porous membrane or the like suitedto this purpose.

[0035] Preferably, the discharging passage's region located downstreamof the filter may be of a volume, for example of 0.05 ml or less,smaller than each drop discharged from said passage. This willcontribute to diminish the quantity of liquid content prone to contactambient air, downstreamly of the filter.

[0036] A cap for enclosing the bottle finish may have a projectionshaped to fit in the discharging passage's portion located downstream ofthe filter. Thanks to this projection, any residue of the liquid contentstagnant downstreamly of the filter will either be repelled forwards outof said passage, or forced back inwards through said filter as the capis mounted. Thus, the mounting of the cap will completely empty theregion of the passage downstream of the filter, not to permit stagnationtherein of ally amount of liquid content.

BEST MODES OF CARRYING OUT THE INVENTION

[0037]FIGS. 1 and 2 show an eyedropper 1 provided in an embodiment ofthe present invention. This eyedropper 1 comprises a laminated butdelaminatable bottle 2 having a finish 2 a and a body 2 b, a plug orstopper (viz., internal cap) 3 having a dispensing nozzle 31, and a cap(viz., external cap) 40. With the body of bottle 2 being compressed by auser, a collyrium (viz., liquid content) held therein will be forcedforwards through a passage 10 formed in the stopper 3, so as to bedropped off the free extremity of a discharging nozzle 31.

[0038] The delaminatable bottle 2 is composed of an outer layer 21 andan inner layer 22. Both the outer and inner layers 21 and 22 havecylindrical finish portions 21 a and 22 a in addition to their bodyregions 21 b and 22 b, which are oval in cross section. In other words,the bottle finish 2 a is a complex of these finish portions 21 a and 22a, and the body 2 b being another complex of these body regions 21 b and22 b. The outer layer 21 may for example be formed of a relatively hardsynthetic resin such as a PET or EVOH, with the inner layer 22 beingmade of another resin (for example a polyolefin such as polyethylene)readily delaminating from the outer layer. An upper end of the innerlayer finish portion 22 a is firmly fixed on an upper end of the outerlayer finish portion 21 a. An inner periphery of the outer layer finishportion 21 a may be knurled longitudinally of the bottle to have groovesat angular intervals so that the inner layer finish portion 22 a willnot become offset relative to the former portion 21 a in a circulardirection.

[0039] A vent hole 4 is formed in the outer layer finish portion 21 a soas to introduce ambient air in between the body regions 21 b and 22 b ofthe outer and inner layer. This vent hole 4 penetrates only the outerlayer 21 sideways, not the inner layer 22. A gap present between the cap40 and the bottle 2 will serve to guide ambient air to the vent hole 4.

[0040] The inner layer body region 22 b is a filmy portion ready tosmoothly deflate as the amount of liquid content decreases. The innerlayer finish portion 22 a is thicker than the body region 22 b so as tomake an elastic behavior.

[0041] A part of the inner layer finish portion 22 a is intended to shutfrom inside the vent hole 4 formed in the outer layer finish portion 21a so that the former portion does normally act as a closing member.However, said inner finish portion 22 a will be pressed and deformedinwards by the atmospheric pressure to open said inlet 4 when a negativepressure is produced between the outer and inner body regions 21 b and22 b, thus serving as a kind of (additional) check valve.

[0042] The inner finish portion 22 a (viz., a closing portion) is ofsuch a thickness and diameter as enabling it to recover its normalposition to close the vent hole 4.

[0043] A round hook 22 c formed integral at a central point of thebottom of the inner layer 22 is in a firm and tight engagement with thebottom center of the outer layer 21, thus inhibiting it from curling up.

[0044] The stopper 3 consists of the nozzle 31, a flange 32 bearingagainst an upper face (viz., end surface) of the bottle finish 2 a, agenerally cylindrical socket portion 34 and a transverse partition 33tightly fitted therein. In the present embodiment, the nozzle 31, flange32 and socket portion 34 are made integral with each other to be aone-piece. The partition 33 is a portion of a sealing cap 5 fitting in alower region of the socket portion 34, and has at its center a valvehole 6.

[0045] Formed between the partition 33 and the proximal part of thenozzle 31 is a cavity or space 9 for accommodation of a filter 7 and a(compulsory) check valve 8. The interior of inner layer 22 communicateswith exterior through the valve hole 6, the space 9 and an axial bore 31a extending( through the nozzle 31, with these three portions or regionsconstituting a discharging passage 10 to discharge the liquid content inthe inner layer 22.

[0046] A membrane filter is used as the filter 7 in the embodiment,though a sintered solid piece, hydrophilic or hydrophobic porous andflat membrane may alternatively be employed as such a filter. In anycase, the filter 7 has to prevent permeation of bacteria and the likefrom the (outer) downstream side to the (inner) upstream side of thefilter. This filter 7 located downstreamly of the check valve 8 andclose to the nozzle 31 in the illustrated embodiment is supported by aseat 50 and held flat thereon. This seat 50 is fit in the space 9 andperforated at 5 1 to keep minute voids in liquid communication with thecavity 9.

[0047] The discharging bore 31 a through nozzle 31 extend from thecenter of filter 7 to the outer (downstream) extremity of the nozzle.The bore 3 la tapered towards the extremity to gradually increase itsdiameter does form an end region of the passage 10, located downstreamof the filter 7. This end region has a volume of 0.5 ml or lesscorresponding to one drop of the collyrium dispensed from the nozzleopening. If the filter 7 is formed of an absorptive material, then anyresidual amount of collyrium will be absorbed therein to rendercompletely vacant the bore 31 a so as to more effectively avoidpropagation of bacteria that would otherwise occur therein.

[0048] The check valve 8 comprises a valve body 11 for closing the valvehole 6 on its downstream (upper) side, which hole constituting oneregion of the discharging passage. This valve body 11 continuesintegrally through thin pieces 13 to a cylindrical member 12 interveningbetween the partition 33 and filter 7, in a fashion shown in FIG. 3. Thecylindrical member 12 functions also to support the filter 7 in placenot to move in any way within the cavity 9 (viz., passage 10). Thesupport 50 for the filter is fitted down in an upper end of this member12.

[0049] The external cap 40 is screwed on outer periphery of the finish 2a of bottle so that the nozzle 31 is sealed up to prevent dust andbacteria from sticking thereto. A projection 41 depending from thecentral inner face of the cap's top will fit in the nozzle bore 31 a soas to fully occupy it, insofar as the cap 40 remains fastened on thebottle finish 2 a.

[0050] In use of the eyedropper 1 provided in the present embodiment andhaving its delaminatable bottle 2 filled with a collyrium, any user willgrip its body 2 b in a direction of its minor axis. The body regions 21b and 22 b of outer and inner layers will thus be depressed in such acentripetal direction so that the collyrium held in the inner layer 22opens the check valve 8 (by displacing its valve body 11) and drop downfrom the end of nozzle 31. If the user ceases to press the delaminatablebottle 2, then the outer layer 21 will recover its normal shape, withthe check valve 8 being closed not to allow backflow of collyrium andflow of ambient air into the inner layer 22. This means that the innerlayer 22 will never restore its original shape but continues to deflateas the collyrium is further dispensed. In more detail, as the outerlayer 21 tends to restore its original shape, a negative pressure willbe produced between the body regions 21 b and 22 b of outer and innerlayers, whereby the atmospheric pressure will temporarily deform theinner layer finish 22 a centripetally to consequently open the vent hole4 formed in the outer layer 21. As a result, a sufficient amount ofambient air flows in between the inner and outer layers 22 and 21through the vent hole 4, to thereby facilitate the outer layer bodyregion 21 b to recover its normal contour. The inner layer finishportion 22 a will simultaneously get out of its temporary inwarddeformation so as to recover its fully cylindrical shape for keeping thevent hole 4 closed.

[0051] The user may resume his or her compressing of the delaminatablebottle 2. However, the air then present between the outer layer body 21b and inner layer body 22 b will not be able to escape outwards becausethe inner layer finish 22 a is still in close contact with the vent hole4 to be closed. The interlayer air thus compressed by the decrease ofthe volume of the deformed outer layer body 21 b will in turn compressthe inner layer body 22 b so that the remainder of collyrium is squeezedout of the inner layer 22, through the passage 10 and dropped again fromthe end of nozzle 31. A little amount of collyrium stays in the nozzlebore 31 a after every operation of using the eyedropper, but its volumeis not larger than one drop of said collyrium and it will be removedcompletely from said bore by mounting the cap 4 on this container.

[0052] A noticeable amount of collyrium, more or less, will stay in thespace (letting the valve body 11 to reversibly open within thecylindrical member 12 in the embodiment) between the partition 34 andfilter 7. However, this filter 7 will exclude the ambient air from sucha stagnant amount of collyrium so as to avoid contamination thereof withbacteria, thus keeping aseptic condition.

[0053] In summary, the present invention employing resins and soft ornonrigid glasses to manufacture the bottle proposes a delaminatablestructure such that its volume (inside the inner layer) will decrease asthe liquid content is consumed. This structural feature excludes ambientair from entering the bottle so that it will be kept sterilized evenonce unsealed. This bottle can be made transparent, if necessary, tosuch a degree as required for eyedroppers. Further, this delaminatablebottle comprises a filter disposed on downstream side of the check valvefor inhibiting inflow of ambient air, and this filter is effective toisolate from the exterior a space in which the valve opens and isclosed. Thus, the liquid content stagnant in that space which isinherent in the delaminatable bottle is now rendered free fromcontamination with bacteria.

1. A discharging container with a filter, the container comprising alaminated bottle and a stopper attached to a finish of the laminatedbottle; the bottle being composed of an outer layer and an inner layerdelaminatable therefrom, with the outer layer leaving a vent hole formedtherein so as to introduce ambient air in between the outer and innerlayers, the stopper leaving a discharging passage formed therein toexude therethrough a liquid content inside the inner layer, the filterbeing disposed together with a check valve in the discharging passageand being located on a downstream side of the check valve.
 2. Adischarging container as defined in claim 1, wherein the check valve hasa valve hole and a valve body for closing the valve hole from itsdownstream side, the valve hole forming a part of the dischargingpassage, wherein the valve body is capable of being displaceddownstreamly of the valve hole to open it, and a free space is definedbetween the valve hole and the filter so as to permit displacement ofthe valve body.
 3. A discharging container as defined in claim 2,wherein the valve body is formed integral with a cylindrical memberdisposed between the valve hole and the filter so that this member holdsthe filter in place in the passage.
 4. A discharging container asdefined in claim 3, further comprising at least one deformable thinpiece to connect the cylindrical member to the valve body continuingtherefrom.
 5. A discharging container as defined in claim 1, wherein thefilter is formed such that bacteria are inhibited from passing from adownstream side to an upstream side of the filter.
 6. A dischargingcontainer as defined in claim 1, wherein the discharging passage has,downstreamly of the filter, a region whose volume is not larger than onedrop of the liquid content being exuded dropwise through said passage.7. A discharging container as defined in claim 1, further comprising acap attachable to the finish, with a projection protruding from the capso as to fit in and engage with a region of the discharging passagelocated downstreamly of the filter, to thereby occupy a cavity definedby and in the region.
 8. A discharging container as defined in claim 1,wherein the inner layer spontaneously deflates as the liquid content isconsumed.
 9. A discharging container as defined in claim 1, wherein theouter layer of the bottle is squeezable and shows an elastic recovery.10. A discharging container as defined in claim 1, wherein the checkvalve is formed to inhibit ambient air from entering the space definedby and in the inner layer, but to allow the liquid content to flowoutwards.
 11. A stopper to be mounted on a finish of a bottle, thestopper comprising: a discharging passage for discharging a liquidcontent of the bottle, a check valve disposed in the dischargingpassage, and a filter also disposed in the discharging passage, whereinthe filter is located on a downstream side of the check valve.
 12. Astopper as defined in claim 11, wherein the check valve has a valve holeand a valve body for closing the valve hole from its downstream side,the valve hole forming a part of the discharging passage, wherein thevalve body is capable of being displaced downstreamly of the valve holeto open it, and a free space is defined between the valve hole and thefilter so as to permit displacement of the valve body.
 13. A stopper asdefined in claim 12, wherein the valve body is formed integral with acylindrical member disposed between the valve hole and the filter sothat this member holds the filter ill place in the passage.
 14. Astopper as defined in claim 13, further comprising at least onedeformable thin piece to connect the cylindrical member to the valvebody continuing therefrom.
 15. A stopper as defined in claim 11, whereinthe filter is formed such that bacteria are inhibited from passing froma downstream side to all upstream side of the filter.
 16. A stopper asdefined in claim 11, wherein the discharging passage has, downstreamlyof the filter, a region whose volume is not larger than one drop of theliquid content being exuded dropwise out of said passage.
 17. A stopperas defined in claim 11, further comprising a cap attachable to thefinish of the bottle, with a projection protruding from the cap so as tofit in and engage with a region of the discharging passage locateddownstreamly of the filter, to thereby occupy a cavity defined by and inthe region.
 18. A stopper as defined in claim 11, wherein the checkvalve is formed to inhibit ambient air from entering the space definedby and in the inner layer, but to allow the liquid content to flowoutwards.